NATURALLY DEGRADABLE PRODUCTS

Abstract: A product, such as a golf or rugby tee or a clay pigeon, is made by compressing together or moulding grass or other plant pieces to form a rigid or semi-rigid structure. Dried grass, together with any additive, is extruded by an extruding machine, and the resulting extrusion is then ground to a small size. Weighed batches of the ground particles are then supplied to a rotary press which makes use of two complementary stamping tools to form a number of products. The resulting products are naturally degradable and do not have to be picked up after use.

Description: "Naturally Decrradable Products" The invention relates to naturally degradable products, such as naturally degradable sports products. When playing rugby, it is sometimes necessary to support the ball in an upright position before the ball is kicked. This is done in a number of ways including, for example, supporting the lower end of the ball in a small pile of sand, or asking another player to support the top of the ball until it is kicked. It is also known to use various plastic tees to support the rugby ball in an upright position. However, such methods suffer from a number of disadvantages. In particular, concentrated areas of sand may cause damage to the playing field, and plastic tees have to be removed from the playing field after use. A similar problem arises from the use of plastic golf tees. Plastic golf tees which are left on golf courses by players can cause damage to the golf course. Furthermore, the presence of such plastic tees on the golf course is unsightly, and considerable time and expense can be involved in collecting and removing the tees. Furthermore, if such plastic tees remain on the golf course, they can cause damage to grass cutting machines. The invention seeks to overcome the disadvantages of the prior art, and also to provide a number of additional advantages. According to the present invention there is provided a method of making a naturally degradable product, the method comprising compressing together or moulding a plurality of plant pieces so as to form a rigid or semi¬ rigid structure. It is preferred that the plant pieces are extruded in a mass, the extruded mass is ground to form fine particles, and the ground particles are compressed together to form a rigid or semi-rigid structure. Alternatively a liquid or viscous material containing processed plant pieces may be moulded within a mould of the desired shape, the liquid or viscous material being allowed to set so as to form a rigid or semi-rigid structure. If required a natural adhesive may be added so as to help bond the plant pieces together. The n a tura l adhesive may comprise glucose or processed animal material, such as fish glue. Other natural materials, such as flour and/or grass seeds, including wheat and barley seeds, may be added to the plant pieces in order to increase the binding of the rigid or semi-rigid structure. It has also been found that wood sap is effective in binding together the plant pieces. It will be appreciated that wood sap may appear automatically as a result of compression of plant pieces if at least some of the plant pieces are formed of wood. However wood sap may also be added as a separate step in the method. Any kind of plant material may be used to produce the plant pieces, including any fruit or vegetable material. For example, the plant pieces may comprise cut grass and/or pieces of bark. Wood shavings, sawdust and/or other wood derivatives are also suitable for use as the plant pieces. Other possibilities for the plant pieces include pieces of coconut, bean, pea, olive and/or citreous products. Preferably, the plant pieces are formed from natural municipal waste, such as garden waste. In this case, the method according to the invention is particularly environmentally friendly in view of the fact that not only is the end product of the method naturally degradable, but the raw materials of the method are formed from materials which would otherwise have gone to waste. Desirably, the naturally degradable product produced according to the method of the invention is at least bio-degradable. The invention also includes within its scope products made according to the above methods. In particular, the method is especially suitable for the production of tees for golf or rugby balls. It will be appreciated that such golf and rugby tees will naturally degrade within time, thus obviating the need for such tees to be manually collected from golf courses and rugby pitches after use. In view of the fact that the tees are formed from a plurality of plant pieces, the natural degradation of the products will be relatively rapid. This is because the products will have a tendency to fragment, thus causing the separate plant pieces to degrade more rapidly. It will be appreciated that, rather than causing damage to the grass as is the case with many plastic tees which are currently available, the tees according to the invention may actually provide the grass with nourishment as a result of their natural degradation. Preferably, the golf or rugby tee is adapted to disintegrate when the ball which is supported by the tee is struck by a player. In order to produce a naturally disintegrating tee, it would be necessary to provide relatively weak binding between the separate plant pieces of the final product. The tees according to the invention also ensure that the ball is supported at a consistent height above any playing surface. Furthermore, the tees provide less resistance than known plastic or solid tees, and therefore are less likely to mark or scratch golf drivers. A further advantage of the tees is that, in view of their propensity to easily fragment, they do not cause damage to grass cutting machines. The invention also provides a naturally degradable flying target, for example for use in clay pigeon shooting. The invention also provides a naturally degradable plant-protecting tube for protecting and/or supporting young plants, such as trees and shrubs, during the early stages of their growth. If required the tube may be impregnated with a pesticide. A particular advantage of this tube is that, once it has been placed around the plant, for example in order to attach the plant to an adjacent supporting post, it will naturally degrade over a period of time, and can therefore be forgotten about after it has been placed in position. The invention also provides a naturally degradable container, for example an egg carton, punnet, hamper or casket. The invention also provides a naturally degradable plant pot made according to any one of the above methods. The plant pot may be treated with fertilisers or pesticides. The invention also provides a naturally degradable solid, rigid or semi-rigid compost block. Such compost blocks would be easier to transport than loose compost. The invention also provides a naturally degradable plant container which may be impregnated with a fertilizing substance and which is adapted to be placed in soil so as to receive the roots of plants, such as house plants or newly planted trees and shrubs, and to fertilise the roots. In order that the invention may be more fully understood, a number of naturally degradable products in accordance with the invention will now be more particularly described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a side view of a golf tee; Figure 2 is a view from above of the golf tee of Figure 1; Figure 3 is a side view of a rugby tee; Figure 4 is a view from above of the rugby tee of Figure 3 ; Figure 5 is a side view of a clay pigeon; Figure 6 is a view from above of the clay pigeon of Figure 5; Figure 7 is a perspective view of a plant- protecting tube in two halves; Figure 8 is a side view of a fertilizer stick; Figure 9 is a side view of a seed pod; Figure 10 is a side view of four fertilizer pellets; Figure 11 is an end view of the four fertilizer pellets of Figure 10; Figure 12 is a side view of an animal supplement lick; Figure 13 is a view from above of the animal supplement lick of Figure 12; Figure 14 is a side view of a cartridge stopper; Figure 15 is a view from above of the cartridge stopper of Figure 14; Figure 16 is a side view of a riot bullet; Figure 17 is a view from above of the riot bullet of Figure 16; Figure 18 is a side view of a seed tile; and Figure 19 is a view from above of the seed tile of Figure 18. Each of the naturally degradable products shown in the drawings is made by a method in accordance with the invention using cut grass as the basic constituent. In this method the grass is first dried, for example in a rotary kiln, until the moisture content is reduced to 10% by weight or less. The cut dried grass is then passed to an extruding machine, optionally after mixing with an additive, such as a fertilizer, if required. The cut dried grass, together with any additive, is then extruded by the machine. In certain applications, for example for fertilizer pellets, the resultant extrusion is simply chopped up to form the end product. However, for most of the illustrated products, the extrusion is then ground to a small particle size, preferably to a particle size of less than 1 mm, and the ground particles are divided into weighed batches each of which is to form one product. The ground particles are then supplied to a rotary press having two complementary stamping tools which together define the shape of a number of the required products. Each batch of ground particles is supplied to a respective recess in one of the tools, and the tools are then mated together and a compression force of approximately 20 tonnes per square inch applied so as to compress the ground particles. After this compression step the resultant shaped products are discharged from the press. In many cases the products are formed substantially exclusively from cut grass without it being necessary to add any substance to the grass to improve adhesion. This is the case more particularly at the beginning of the grass growing season when the grass has a relatively high sugar/starch content. However it may under certain circumstances be necessary to add glucose to the cut dried grass, for example in a proportion of less than 2% by weight, in order to improve the adhesive quality of the grass. Where cut dried grass is not plentiful, the grass may be supplemented by other plant pieces or replaced altogether by other plant pieces, such as pieces of fruit or vegetable material, pieces of bark, wood shavings or sawdust, for example. If necessary peat or peat substitute material may also be used as a basic constituent. In this case various types of additive may be necessary or desirable to improve adhesion, such as processed animal material, flour, wood sap or cereal/grass seeds. The various types of naturally degradable product shown in the drawings and produced by the above described method will now be described. The golf tee 1 shown in Figures 1 and 2 is of solid, generally conical construction having a flat base portion 2 and a concave recess 4 at its apex and having a height of about 2.5 cm. The recess 4 is adapted to receive and support a golf ball, and the tee as a whole is adapted to disintegrate when the golf ball is struck during play. Figures 3 and 4 show a rugby tee 3 which is similar in form to the golf tee 1 except that it has a steeper side wall and larger recess 4 and is of larger size, having a base portion 2 of a diameter of about 10 cm, and is formed with a larger recess 4 for supporting the lower end of a rugby ball. The clay pigeon 5 shown in Figures 5 and 6 is in the form of a shaped circular disk having a diameter of about 10 cm and having convex upper and lower sides 6, as is conventional in clay pigeon shooting. The tree/shrub protector 7 shown in Figure 7 is of generally tubular form and comprises two halves 8 which may be fastened together around the lower trunk of a tree or shrub. Figure 8 shows a fertilizer stick 9 which has a round cross-section and a length of about 15 cm. The fertilizer stick 9 is intended to be placed in the ground or in the growing medium of a plant pot in order to slowly release fertilizer for encouraging plant growth, and is impregnated with a slow-acting fertilizer which may contain nitrogen, phosphate and potassium. The constituents of the fertilizer, may be added to the base constituent either before or after the extrusion process. Figure 9 shows a seed pod or container 10 which is of generally inverse conical shape having a height of about 2.5 cm and having a recess 11 in its top. The seed pod 10 is impregnated with a slow-acting phosphate fertilizer, such as calcium aluminium phosphate with the addition of 34% by weight of phosphorous pentoxide (P0 5 ) . The seed pod 10, which may also be impregnated with a pesticide if required, is intended to be implanted in the ground with a seed contained in the recess 11 so that, as a plant grows from the seed, the plant roots grow through the pod 10 and are fertilized thereby. The fertilizer pellets 12 shown in Figures 10 and 11 are produced simply by extruding the dried cut grass to which nitrogen, phosphate and potassium has been added, and chopping up the resulting extrusion. The animal supplement lick 13 shown in Figures 12 and 13 is impregnated with any required feed additives, such as phosphorous, and may be of various forms and sizes depending on the animals to be fed, for example cattle, pigs or poultry. The cartridge stopper 14 shown in Figures 14 and 15 is intended to close off the end of a shotgun cartridge. The riot bullet 15 shown in Figures 16 and 17 is provided at its head with a cross-shaped recess 16 which is intended to ensure that the bullet shatters on impact. The seed tile 17 shown in Figures 18 and 19 is impregnated with a slow-acting fertilizer, such as phosphate, and also contains seeds, such as grass seeds, so that the seed tile may be laid on the ground, in the manner of a lawn turf for example, so as to serve as a growing medium. Other naturally degradable products can also be produced by such a method, although these are not illustrated. For example pre-formed containers for packaging of items, such as electrical equipment, ornaments and the like, may be formed in this manner, and are of course easily disposed of after use. In all of these applications the product will degrade naturally with time so that it does not adversely affect the environment.

Claims: CLAIMS 1. A method of making a naturally degradable product, the method comprising compressing together or moulding a plurality of plant pieces so as to form a rigid or semi-rigid structure. 2. A method according to claim 1, wherein the plant pieces are extruded in a mass. 3. A method according to claim 2, wherein the extruded mass is ground to form fine particles. 4. A method according to claim 3, wherein the ground particles are compressed together to form a rigid or semi¬ rigid structure. 5. A method according to claim 1, wherein a liquid or viscous material containing processed plant pieces is moulded within a mould of the desired shape, and the liquid or viscous material is allowed to set so as to form a rigid or semi-rigid structure. 6. A method according to any preceding claim, wherein a natural adhesive is added so as to help bond the plant pieces together. 7. A method according to any preceding claim, wherein the plant pieces comprise cut grass and/or pieces of bark. 8. A naturally degradable product made by a method according to any preceding claim. 9. A product according to claim 8, being a tee for a golf or rugby ball, or a clay pigeon, or a cartridge stopper, or a riot bullet, or a plant protector, or a plant pot, or a container, or a compost block. 10. A product according to claim 8, impregnated with a fertilizing and/or nutritional and/or pesticide substance and being a fertilizer, or a plant container, or a seed tile, or an animal supplement lick.

Inventors: RODERICK JOHN KENNETH, RODERICK, JOHN, KENNETH
Applicants: ECO PRESENCE LTD, RODERICK JOHN KENNETH, ECO PRESENCE LIMITED, RODERICK, JOHN, KENNETH
Application year: 1994
Main classification: A63B57
IPC codes: A63B57